The present invention relates to a delivery control device, a data delivery system, a delivery control method and to, for example, a technique for delivering data simultaneously to a number of reception terminals.
In a limited area such as a large event site e.g., a stadium or a hall, there has been a demand for a technique that delivers data such as video of the site in real time to a number of visitors, for example, tens of thousands of visitors. In order to realize such a data delivery technique, it is important that the number of reception terminals will not exceed the capacity of a router.
Japanese Unexamined Patent Application Publication No. 2014-155072 describes a task that attempts to reduce the number of references to an ARP (Address Resolution Protocol) table so as to increase the speed of network communications. Japanese Unexamined Patent Application Publication No. 2014-155072 further discloses a configuration in which a router includes a connection management table that holds relationships between IP addresses and MAC addresses in addition to the ARP table that holds correspondence relationships between the IP addresses and MAC addresses. This eliminates the need for an access to a main memory that stores the ARP table at the time of transmitting packets and the need for a search process that searches the ARP table for a target entry, thereby reducing the processing load on the router, and thus achieving faster TCP communications.
Japanese Unexamined Patent Application Publication No. 2003-348093 describes a task that attempts to eliminate the need to change an IP address setting of a server application at the time of switching an NIC (Network Interface Card) and the need for the server application to issue a request for switching the NIC. Japanese Unexamined Patent Application Publication No. 2003-348093 further discloses a configuration in which NIC management means 31 assigns registered IP addresses to NICs 41 and 51 that are inside a communication processing device 30, and manages correspondences between the IP addresses and MAC addresses 42 and 52 that have been assigned to the NICs 41 and 51 in an NIC/IP address correspondence table 32. The NIC management means 31 includes a function of detecting a failure of the NIC 41 or 51 and a function of, when the failure in the NIC 41 or 51 is detected, rewriting the NIC/IP address correspondence table 32 to change the assignment of the IP address that has been assigned to one of the NICs 41 and 51 in which the failure has been detected so that the IP address is assigned to another one of the NICs 41 and 51. In this way, it is possible to switch the MAC address while fixing the IP address when a failure occurs, thereby reducing the processing time taken to switch the NICs.